Conventionally, a technology related to program execution status display is available in which thread objects, which represent threads executed based on the execution traces of a software program, and events are displayed on a two-dimensional plane including a time axis and a thread axis. This technology has an area for displaying the activities regarding the overall execution status of the software program and an area for displaying a detailed execution status of a specific range using the thread axis and the time axis; and provides the user with a function of specifying the specific area from the area for displaying the overall execution status. As a result, detailed information about a specific location can be displayed in an interactive manner from the overall execution status of the software program.
Consider a case in which, during program development, a program developer displays the execution status of the software program for the purpose of confirmation of operations and optimization of the performance. In that case, the program developer understands the changes occurring in the execution of the software program in response to the changes made to the parameters affecting the behavior of the program source code, the input data, and the program execution environment; and accordingly verifies the operations and examines the effects on the performance. Besides, the program developer can figure out the changes occurring in the execution operations of the software program and the changes occurring in the performance in response to the execution of the same software program for a plurality of number of times under the same execution environment; and can accordingly verify the operations and examine the effects on the performance.